Lectures Watched
Since January 1, 2014
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My Notes on Massive Open Online Course:
Analyzing the Universe
Using publicly available data from NASA of actual satellite observations of astronomical x-ray sources, we explore some of the mysteries of the cosmos, including neutron stars, black holes, quasars and supernovae.
Notes on 3 Lectures I Watched in This Course:
The Nature of Images
Image Formation
Capturing Images of X-Ray Sources from Space
2 People I Have Learned About in this Course:
John Adams Whipple (1822-1891)
Early American photographer who pioneered astronomical and night photography known for his extraordinary early photographs of the moon
  • first in the United States to manufacture the chemicals used for daguerreotypes
  • first to produce images of stars other than the sun (Vega and Mizar-Alcor stellar system)
Pierre de Fermat (1601-1665)
Amateur mathematician who developed the principle that the path taken between two points by a ray of light is the path that can be traversed in the least time
  • Fermat's principle
  • responsible also for its derived principle that a light ray incident upon a reflective surface will be reflected at an angle equal to the incident angle
  • both principles important in the manufacture of lenses for telescopes and cameras
  • given credit for early developments that led to infinitesimal calculus
  • together with René Descartes, Fermat was one of the two leading mathematicians of the first half of the 17th century
  • Isaac Newton wrote that his own early ideas about calculus came directly from Fermat's way of drawing tangents
  • officially only an amateur mathematician, Fermat worked as a lawyer at the Parliament of Toulouse, France
1 Vocabulary Words I Learned in this Course:
daguerreotype, n. the first publicly announced photographic process and the first to come into widespread use during the early 1840s  ""The mind with a memory" are what the first daguerreotypes were called."